Great !!! They taught this at school, but the instructor did it just flying without explanation in a refrigeration box. Yours was more thoroughly! Some day I would do it that confident. Hope your boy is back on his feet !!! ❤
that's how I do it. I wish I would have found these videos when i started about three years ago. I learned more of three of your videos than I did listening to a guy saying he's done this for 42 year😂
I usually pump down with the unit still running I close off the high side first then as the low pressure side drops I close it off then quickly shut of the unit kind of the same method you just closed off the high side while the unit was off I didn’t even know you could do that great video
Very informative and clear video. I’m an apprentice and although I’ve learned how to do this I often forget the step process for it. I have to do things several times before I actually nail down the method
YES! That's why I am here! Thanks Tad! I just Love Learning A/C Systems. Liked, Subscribed, and a Member of your Training. So much to Know and do it right, and Safe!
Good video, I just joined to be a member and I have watched a lot of your videos. I live in Maynardville Tn and had a hvac business about 7 years ago and came down with cancer. I've been in the commercial part installing duct work for a Shoffners Mechanical and was a foreman for many years. I enjoyed working for myself and watching your videos helps me remember things that I would have forgotten. Keep up the good work.
Thank you Jimmy Really appreciate you becoming a member Send me an email tadfuller1@gmail.com If you need any of my Guides If you need help with the project let me know
This is great, the best video on this subject I've found. Newbie question. When the service valve is open you're only reading pressure on the high or low side of the system. When they are closed they are only reading pressure on the evap side. Correct? At this point you'd do your nitrogen purge, repair, pressure test, evac and recharge? Question 2: Can you do a video on how to release the refrigerant into the system once the repair has been made? (Or is as simple as opening the valves and turning the compressor on?)
One important thing that didn’t apply here but does apply to many systems. Micro-channel coils are increasingly more common, and many of those can’t be pumped down without risking coil rupture. I also recently had a technician attempt to do a “reverse pump down”, thinking he could trap the refrigerant in the air handler by closing the suction service valve. As you can guess, that didn’t work out the way he expected. Can it work? Yes, kind of, but only on a heat pump, but there’s a whole different process he was unaware of and hadn’t been trained on.
I need that info for reverse pump down - Do you know? Or the procedure? Ppl think I’m crazy for even asking! But a long time ago in school I remember the instructor said it could be done but needed to be careful! He never showed us how tho!
@@tonywiggins8073 it’s done in heat mode. You close the small service valve, which will be liquid that was just condensed by the air handler. In heat mode the large line isn’t suction, it’s discharge, so you’ll need to put your gauge on the common suction tap, and close the large service valve when it gets as low as it’s going to get. It’s going to subcool and stack liquid refrigerant inside the air handler and trap it there when both service valves are closed. You don’t have a receiver or accumulator in the air handler so it’s only going to hold as much as the coil holds. You will still need to recover the rest to a recovery cylinder. Will From being able to change the liquid line filter dryer unless it’s on the compressor side of the service valves. Best case, you’ll be able to “reverse pump down “about 60 to 70% of the refrigerant, at most. And, again, don’t even try it with a microchannel coil.
@@PeteGaughenbaugh1 Well I was close! 🤣🤣Just trying to figure out the procedure on my own & how the HP cycle worx! But I didn’t know about the micro channel problem )Good to know). So look like I’ll be recovering it bc it’s a Goodman micro channel ! 🤬. Thank you for the information! 👍😎
Yo bro im going to be watching a lot of your videos to keep myself on top of this residential heating and cooling game. You're explanations help my smooth brain understand these concepts. I definitely have some holes in my knowledge, and these videos are helping a lot to fill them in.
That's the exact question I have. I have an ancient R-22 system but don't own gauges and I need to pump it down to remove the furnace, coil, and coil box to repair the floor decking underneath. I had a new furnace installed 3 years ago and it was upgraded to a high efficiency. When the installers ran the PVC pipes to the roof they didn't install the correct cap and worse, they didn't use a finger to form the silicone caulk around the pipes. Basically the new hire with low experience (not being mean...he was new) put an O-ring around the pipes but it never even touched the pipes. Skip ahead 18 months and the condensate pump sitting in front of the furnace on the floor died and flooded the floor. That's when I discovered all the things done wrong during the installation. Rain and snowmelt had been silently running down the pipes, through the furnace behind the front cover out of sight, and down and out the base around the coil box. Then on down underneath to the insulation (my home is a double wide manufactured) which got saturated and half water and moisture that proceeded to rot the decking. I went round and round with the installer and their insurance company and got nowhere. A lot of time was chewed up following the complaint and investigation processes. At that time I developed heart problems and had a series of heart attacks which lead to getting a pacemaker and then Feb 22nd 2024 I had a stroke. That lead to getting a catheter ablation in June of 24. I kept detailed notes, letters, emails, time/date stamped pictures and have videos showing the water running down during a storm. I didn't contact my homeowners insurance company because at first I was following the ridiculous time eating procedures, and then I didn't dare take on the stress of getting back into battle. So currently the floor decking under the vinyl flooring is so sagged that when the blower runs I can smell a musty mildew coming out of all vents. Obviously the ducting has dropped and disconnected from the coil box. Because I'm a 66 year old disabled widower my days of crawling around in the crawl space are over. My dilemma is whether to try and get my insurance to go after the installer on my behalf, or take on the not small project of removing the furnace and nearby 435lb gas water heater, removing the studs and drywall walls of the mechanical closet to get at all of the damaged flooring and replace as necessary. Not something I look forward to doing all alone with a bum ticker. Old guy long, rambling story aside, can I pump it back without gauges and just wait 5 minutes or so after closing the high side? I know, not ideal at all but any of the stupidly expensive R-22 that I can save is more money (for things like food) next year when I get ready to use the AC again. 😂 Is there any danger to the compressor if I guestimate too long and the high pressure side sits at zero too long?
You cannot pump it down unless the compressor is operating. If it's not operating, then just close the valves and recover what's in the line sets and coil
@@TaddyDigest Haha - I know how to do that, but I’m interested in how to do a reverse pump down! And how to do it properly! Knowledge is power & it’s always to learn new tricks and techniques! And you seem like the guy to go to! You really know your stuff! 👍 A Master at his craft! 👍👍
Hey Taddy, this may sound like a dumb question but how would I wire in a float switch to a indoor unit that has a board. Would I just tie one end of the float switch's wiring with the red wire on the R terminal on the board. That would kill power to condenser. Then for the transformer wire to kill power to thermostat, I would see where it goes into the board?
Say a 410a unit came pre charged for 15'. The run to coil is 50' total. Leaving an additional 35'. You initially had to add 1lb 5oz of additional refrigerant to the system for the additional lineset. Would you be able to pump down that additional 21ounces into the condenser as well?
Usually no, it’ll take what it will take but most of the time the pressure wont go all the way to zero if there was an additional add of refrigerant. You’ll have to recover the rest.
The long winded racheting to close the Suction valve, ie pump down is reach just a few cranks and its closed, kill power done. On the other hand you perform pump down then start closing the Suction valve you'll be cranking for a while to close it. It's just a way I actually learned from HVAC GUY CURTIS I tried it and it worked well.
Thanks for video , I work on refridge drinks machines so only small compressors and systems . But I would like to move on to more air con stuff after I am qualified would this be possible or do I need to learn all this again about air con systems ?
If you had extra long line sets along with the extra required refrigerant, are there any concerns about it all fitting in the outside unit? Hmm, now that I think about it, I guess not. I imagine that the accumulator tank is sized to match the max line set length. Am I right about that?
New DIY'er here - I had a new precharged mini split I installed and electrician came in to update the breaker, put a 240v breaker in when appliance was 115v (it was my fault). We all know what happened after that. Since the Unit is now a toaster I am assuming I can do the same steps here but with a Vacuum to pump it down into the unit right? I was hoping to use the unit itself to store the eco R-410 and store it when I uninstall and save the refrigerant. I bought the same pre charged unit just at the right voltage, assuming its not "Dirty" and can be resused down the road when this one eventually leaks? My gut tells me no :), my heart wants to believe it will.
I'm trying to pump down a straight Ac Goodman 4ton 410a system how come it keeps making a loud swooshing noise when it gets to 50psi and then the pressures go back to 115psi is there and internal pressure relief valve because the system doesn't have any high or low pressure switches
Hi and thanks for your videos, I have located a small leak on my 20 year old evaporator is it safe to just open the condenser lines to release the refrigerant back to the system, after repairing the leak, I don't have a vacum pump.
What would you do with the condensers that don’t have a board with the low pressure switch but seem to have a little pressure switch built-in to the compressor? And even holding down contactor manually it still cuts out compressor on low pressure?
I was pumping a 3 ton Down today 410A txv system. I closed the liq line valve and when suction got down to 50 psi, the compressor started hissing and pressure went back up. It has pressure switches so I was pushing the contactor. I ended up recovering and pulled 4 lbs out of it. Wasn’t overcharged. Any idea on why it wouldn’t pull down? After when I put the charge in, it ran perfectly.
@@BillyN31 compressors dont like this being done. It went into bypass, all you can do is recover the rest. I usually go ahead time the suction valve being closed exactly when the compressor pumps down to zero. The linger it runs while sitting at zero the worse it is for the compressor.
You also should of had the indoor fan running while doing this... I mean... technically you can get away with what's shown, but you're missing a few steps that COULD cause issues with someone else. Best to show every step thoroughly.
@@TaddyDigest Yes sorry. So you need some heat load into the refrigerant to be sure it all boils off. This is just a 99.9% guarantee you get it all. You're method is... I'd say 90% guarantee. Just playing it safe.
I know you are a good technician and I truly like your videos, but this time you messed up. 1st, you heated up the compressor by letting the suction line pressure go to vacuum for an extended time, remember compressors are refrigerant cooled. 2nd, the compressor sucked up all the air existing inside the blue hose and I am sure you did not purge it, and even if you did, your pump down sucked up potential air exiting previously inside the system. You should always stop the pump down at a positive 15 to 25 psig, and this means just a tiny bit of vapor that you end up releasing in the air when you open up the system.
> this means just a tiny bit of vapor that you end up releasing in the air when you open up the system. I can see the logic of what you suggest, but the practice is likely an offence contrary to 40 CFR § 82.154 and 42 USC 7671g(c)(1), with criminal penalties as prescribed by 42 USC §7413(c)(1). Something similar applies in the EU, UK, Canada and, I gather, even China and India.
You can run into a negative vacuum for a couple minutes and you won't burn your compressor or windings, it's actually best practice to do so when you pump down into the high side (around +/- - 2PSIG, what he did in that regard was correct. Yes he probably didn't purge the line and some non condensables got mixed in, BUT if you find the highest point in your system and relief valve it, you can purge all non condensables, as that is not illegal to do at least according to the EPA as long as it is either a safe gas to release or in very small amounts just as if you were to connect to a valve with gauges.
@@StrixTechnicaI don't know about other countries but in America a small or neglibile amount of vapor release is not a punishable offense, although the EPA is not clear about what a small amount is there are conditions and scenarios that are allowed and in this case it would also be allowed
I was trying to pump down a new york 5 ton unit for a repair and could not get the condensor to down I used the same method as you are showing here but I think there must be too much refrigerant in it I hear the pressure relief have you ever come across this thanks.
Great !!!
They taught this at school, but the instructor did it just flying without explanation in a refrigeration box.
Yours was more thoroughly!
Some day I would do it that confident.
Hope your boy is back on his feet !!!
❤
Excellent!
that's how I do it. I wish I would have found these videos when i started about three years ago. I learned more of three of your videos than I did listening to a guy saying he's done this for 42 year😂
Same bro fuck going inside and dealing with thermostat.
I usually pump down with the unit still running I close off the high side first then as the low pressure side drops I close it off then quickly shut of the unit kind of the same method you just closed off the high side while the unit was off I didn’t even know you could do that great video
Very informative and clear video. I’m an apprentice and although I’ve learned how to do this I often forget the step process for it. I have to do things several times before I actually nail down the method
Glad it was helpful!
YES! That's why I am here! Thanks Tad! I just Love Learning A/C Systems. Liked, Subscribed, and a Member of your Training. So much to Know and do it right, and Safe!
Never heard of anyone forgetting to open the valves 😅 doesn’t surprise me though haha nice video bro! 👊🏼
Thanks bro
Sweet content keep up the great work and keeping techs informed!! Your content is better than trade school by far haha!
Glad to hear that thank you so much please keep watching
Best explanation available via internet. Thanks for being thorough and understandable.
Wow, thanks! your welcome 🙏
Good video, I just joined to be a member and I have watched a lot of your videos. I live in Maynardville Tn and had a hvac business about 7 years ago and came down with cancer. I've been in the commercial part installing duct work for a Shoffners Mechanical and was a foreman for many years. I enjoyed working for myself and watching your videos helps me remember things that I would have forgotten. Keep up the good work.
Thank you Jimmy
Really appreciate you becoming a member
Send me an email
tadfuller1@gmail.com
If you need any of my Guides
If you need help with the project let me know
very nice explanation. you're a good instructor
Thank you my friend I appreciate you watching
Please consider joining and becoming a member
Since I follow you , I learned a lot, thanks Tady.
Excellent news brother. Thank you so much for watching
Great video teddy !! I loved closed loop systems!!!!!! Wahoooooo
Thanks, that was really clear and helpful
This is great, the best video on this subject I've found. Newbie question. When the service valve is open you're only reading pressure on the high or low side of the system. When they are closed they are only reading pressure on the evap side. Correct? At this point you'd do your nitrogen purge, repair, pressure test, evac and recharge? Question 2: Can you do a video on how to release the refrigerant into the system once the repair has been made? (Or is as simple as opening the valves and turning the compressor on?)
yes and yes, and it's very simple to open the valves and turn the thermostat to cool
One important thing that didn’t apply here but does apply to many systems. Micro-channel coils are increasingly more common, and many of those can’t be pumped down without risking coil rupture.
I also recently had a technician attempt to do a “reverse pump down”, thinking he could trap the refrigerant in the air handler by closing the suction service valve. As you can guess, that didn’t work out the way he expected. Can it work? Yes, kind of, but only on a heat pump, but there’s a whole different process he was unaware of and hadn’t been trained on.
I need that info for reverse pump down - Do you know? Or the procedure? Ppl think I’m crazy for even asking! But a long time ago in school I remember the instructor said it could be done but needed to be careful! He never showed us how tho!
@@tonywiggins8073 it’s done in heat mode. You close the small service valve, which will be liquid that was just condensed by the air handler. In heat mode the large line isn’t suction, it’s discharge, so you’ll need to put your gauge on the common suction tap, and close the large service valve when it gets as low as it’s going to get. It’s going to subcool and stack liquid refrigerant inside the air handler and trap it there when both service valves are closed.
You don’t have a receiver or accumulator in the air handler so it’s only going to hold as much as the coil holds. You will still need to recover the rest to a recovery cylinder. Will From being able to change the liquid line filter dryer unless it’s on the compressor side of the service valves. Best case, you’ll be able to “reverse pump down “about 60 to 70% of the refrigerant, at most. And, again, don’t even try it with a microchannel coil.
@@PeteGaughenbaugh1 Well I was close! 🤣🤣Just trying to figure out the procedure on my own & how the HP cycle worx! But I didn’t know about the micro channel problem )Good to know). So look like I’ll be recovering it bc it’s a Goodman micro channel ! 🤬. Thank you for the information! 👍😎
Learned this the hard way early on with another guy. We tried to pump down a york microchannel and it blew the compressor
Great video! Could you also close both valves while the unit is off if you have a low pressure switch?
yes While the unit is off
Great video. Thanks for sharing 🎉
This was explained so well, thank you Ted💪🏼💪🏼💪🏼
My pleasure!
Pump down Instruction simplified!
Like it bro! Very informative
thank you brother
Thank you
Yo bro im going to be watching a lot of your videos to keep myself on top of this residential heating and cooling game.
You're explanations help my smooth brain understand these concepts. I definitely have some holes in my knowledge, and these videos are helping a lot to fill them in.
Awesome thank you so much for watching my friend
Please consider joining level three members get access to all my members only videos about h v a c
Oooo ill have to check that out.
If you have to push a contactor in use an insulated hand tool
good tip for safety 👍
Great job tad very informative video
Thank you brother tom
Can I do this without gauges? Say when the indoor unit stops cooling I’ll close the last valve?
@@EREBO95 not a good idea. Some guys do it from sound but unless you’re replacing the whole cooling system I wouldn’t.
That's the exact question I have. I have an ancient R-22 system but don't own gauges and I need to pump it down to remove the furnace, coil, and coil box to repair the floor decking underneath. I had a new furnace installed 3 years ago and it was upgraded to a high efficiency. When the installers ran the PVC pipes to the roof they didn't install the correct cap and worse, they didn't use a finger to form the silicone caulk around the pipes. Basically the new hire with low experience (not being mean...he was new) put an O-ring around the pipes but it never even touched the pipes.
Skip ahead 18 months and the condensate pump sitting in front of the furnace on the floor died and flooded the floor. That's when I discovered all the things done wrong during the installation.
Rain and snowmelt had been silently running down the pipes, through the furnace behind the front cover out of sight, and down and out the base around the coil box. Then on down underneath to the insulation (my home is a double wide manufactured) which got saturated and half water and moisture that proceeded to rot the decking.
I went round and round with the installer and their insurance company and got nowhere. A lot of time was chewed up following the complaint and investigation processes.
At that time I developed heart problems and had a series of heart attacks which lead to getting a pacemaker and then Feb 22nd 2024 I had a stroke. That lead to getting a catheter ablation in June of 24.
I kept detailed notes, letters, emails, time/date stamped pictures and have videos showing the water running down during a storm. I didn't contact my homeowners insurance company because at first I was following the ridiculous time eating procedures, and then I didn't dare take on the stress of getting back into battle.
So currently the floor decking under the vinyl flooring is so sagged that when the blower runs I can smell a musty mildew coming out of all vents. Obviously the ducting has dropped and disconnected from the coil box. Because I'm a 66 year old disabled widower my days of crawling around in the crawl space are over.
My dilemma is whether to try and get my insurance to go after the installer on my behalf, or take on the not small project of removing the furnace and nearby 435lb gas water heater, removing the studs and drywall walls of the mechanical closet to get at all of the damaged flooring and replace as necessary. Not something I look forward to doing all alone with a bum ticker.
Old guy long, rambling story aside, can I pump it back without gauges and just wait 5 minutes or so after closing the high side? I know, not ideal at all but any of the stupidly expensive R-22 that I can save is more money (for things like food) next year when I get ready to use the AC again. 😂 Is there any danger to the compressor if I guestimate too long and the high pressure side sits at zero too long?
By the way, I subscribed. Great video! Clear and consise without any bs wastes of time.
Hello how do you pump down if compressor is not operating ? , replacing a split ? Any way to do with vac pump ? Or is that a sucking only action ??
You cannot pump it down unless the compressor is operating. If it's not operating, then just close the valves and recover what's in the line sets and coil
Any vid, info, or procedure to do a reverse pump down to the indoor coil & line set to do a compressor change out??
use a recovery machine
@@TaddyDigest Haha - I know how to do that, but I’m interested in how to do a reverse pump down! And how to do it properly! Knowledge is power & it’s always to learn new tricks and techniques! And you seem like the guy to go to! You really know your stuff! 👍 A Master at his craft! 👍👍
Do u leave both side of gages open during?
no sir
@@TaddyDigest serious question, just high side open?
When using a drill on the service valve, just set the clutch on the drill to like 5. You will be fine.
Good advice thank you
Hi my friend
The way I do it when I get to 0 I close the valve and I pull out the disconnect 😅😅😅
Hey Taddy, this may sound like a dumb question but how would I wire in a float switch to a indoor unit that has a board. Would I just tie one end of the float switch's wiring with the red wire on the R terminal on the board. That would kill power to condenser. Then for the transformer wire to kill power to thermostat, I would see where it goes into the board?
I will do a video on that for you
Say a 410a unit came pre charged for 15'. The run to coil is 50' total. Leaving an additional 35'. You initially had to add 1lb 5oz of additional refrigerant to the system for the additional lineset.
Would you be able to pump down that additional 21ounces into the condenser as well?
Usually no, it’ll take what it will take but most of the time the pressure wont go all the way to zero if there was an additional add of refrigerant. You’ll have to recover the rest.
I was really curious is there any possible way the compressor can possibly blow out if it reaches 0psi while closing the suction line ?
How do you release the refrigerant back to the system.
Do i open up suction line first?
yes
Question. How do you keep the compressor from bypassing internally?
I usually like to close the Suction valve then backing it off 7 turns before I start the pump down. Great video!
That's a good idea!
What the reason for your method?
The long winded racheting to close the Suction valve, ie pump down is reach just a few cranks and its closed, kill power done. On the other hand you perform pump down then start closing the Suction valve you'll be cranking for a while to close it. It's just a way I actually learned from HVAC GUY CURTIS I tried it and it worked well.
I woulda partially closed the vapour line so you can time it better when the pressure drops to zero.
Thanks for video , I work on refridge drinks machines so only small compressors and systems . But I would like to move on to more air con stuff after I am qualified would this be possible or do I need to learn all this again about air con systems ?
Totally possible you already have a Experience
If you had extra long line sets along with the extra required refrigerant, are there any concerns about it all fitting in the outside unit? Hmm, now that I think about it, I guess not. I imagine that the accumulator tank is sized to match the max line set length. Am I right about that?
New DIY'er here - I had a new precharged mini split I installed and electrician came in to update the breaker, put a 240v breaker in when appliance was 115v (it was my fault). We all know what happened after that. Since the Unit is now a toaster I am assuming I can do the same steps here but with a Vacuum to pump it down into the unit right? I was hoping to use the unit itself to store the eco R-410 and store it when I uninstall and save the refrigerant. I bought the same pre charged unit just at the right voltage, assuming its not "Dirty" and can be resused down the road when this one eventually leaks? My gut tells me no :), my heart wants to believe it will.
I'm trying to pump down a straight Ac Goodman 4ton 410a system how come it keeps making a loud swooshing noise when it gets to 50psi and then the pressures go back to 115psi is there and internal pressure relief valve because the system doesn't have any high or low pressure switches
Hi and thanks for your videos, I have located a small leak on my 20 year old evaporator is it safe to just open the condenser lines to release the refrigerant back to the system, after repairing the leak, I don't have a vacum pump.
You definitely need a vacuum it down You need to put nitrogen in it first and then vacuum it down
Go check out a couple more on my videos. The most recent will show you how I pull a vacuum
Thank you
Awesome ted!!
Glad you enjoyed it
i cant get the high side to turn down,probally the lastguy who worked on the unit stripped the valve. what can i do to pump it down now.
What would you do with the condensers that don’t have a board with the low pressure switch but seem to have a little pressure switch built-in to the compressor? And even holding down contactor manually it still cuts out compressor on low pressure?
That's impossible
If you hold down the contact or it can't shut the contact or off
@@TaddyDigest ah ok so with those style compressors with integrated LPS you can’t pump them down?
What if it’s a heat pump? Still just run it in cooling? Don’t the reversing valves in yorks energize in cooling ?
yes they do
Was that R22 or R410?
410A
I was told u can’t pump down 410, bc of the scroll compressor & the high pressures
Saw on u tube that u should not pump down a scroll compressor because u can burn out the compressor
I was pumping a 3 ton Down today 410A txv system. I closed the liq line valve and when suction got down to 50 psi, the compressor started hissing and pressure went back up. It has pressure switches so I was pushing the contactor. I ended up recovering and pulled 4 lbs out of it. Wasn’t overcharged. Any idea on why it wouldn’t pull down? After when I put the charge in, it ran perfectly.
@@BillyN31 compressors dont like this being done. It went into bypass, all you can do is recover the rest. I usually go ahead time the suction valve being closed exactly when the compressor pumps down to zero. The linger it runs while sitting at zero the worse it is for the compressor.
@@royrollins8987 I pump down systems all the time. No issues
You cant pump down scroll compressors
With a scroll compress the internal release won't let it pump down all the way that's what I came across I may be wrong
This was a scroll compressor
@@TaddyDigest You risk damaging a scroll compressor when doing this....
You also should of had the indoor fan running while doing this... I mean... technically you can get away with what's shown, but you're missing a few steps that COULD cause issues with someone else. Best to show every step thoroughly.
Tell me what the indoor fan does
Am I missing something
You think the indoor fan has something to do with the refrigerant pumping into the Outdoor unit
@@TaddyDigest Yes sorry. So you need some heat load into the refrigerant to be sure it all boils off. This is just a 99.9% guarantee you get it all. You're method is... I'd say 90% guarantee. Just playing it safe.
Got it thank you for clarifying my friend
@@TaddyDigest No problem. Great channel.
Sometimes it works, sometimes it doesn't.
I know you are a good technician and I truly like your videos, but this time you messed up. 1st, you heated up the compressor by letting the suction line pressure go to vacuum for an extended time, remember compressors are refrigerant cooled. 2nd, the compressor sucked up all the air existing inside the blue hose and I am sure you did not purge it, and even if you did, your pump down sucked up potential air exiting previously inside the system. You should always stop the pump down at a positive 15 to 25 psig, and this means just a tiny bit of vapor that you end up releasing in the air when you open up the system.
So you're telling me that a refrigeration system is an open loop instead of a closed loop system
That's what you're insinuating
I don't understand
> this means just a tiny bit of vapor that you end up releasing in the air when you open up the system.
I can see the logic of what you suggest, but the practice is likely an offence contrary to 40 CFR § 82.154 and 42 USC 7671g(c)(1), with criminal penalties as prescribed by 42 USC §7413(c)(1). Something similar applies in the EU, UK, Canada and, I gather, even China and India.
@@StrixTechnicaright on point. I know someone who didn’t know any better and got arrested for releasing into air
You can run into a negative vacuum for a couple minutes and you won't burn your compressor or windings, it's actually best practice to do so when you pump down into the high side (around +/- - 2PSIG, what he did in that regard was correct. Yes he probably didn't purge the line and some non condensables got mixed in, BUT if you find the highest point in your system and relief valve it, you can purge all non condensables, as that is not illegal to do at least according to the EPA as long as it is either a safe gas to release or in very small amounts just as if you were to connect to a valve with gauges.
@@StrixTechnicaI don't know about other countries but in America a small or neglibile amount of vapor release is not a punishable offense, although the EPA is not clear about what a small amount is there are conditions and scenarios that are allowed and in this case it would also be allowed
I was trying to pump down a new york 5 ton unit for a repair and could not get the condensor to down I used the same method as you are showing here but I think there must be too much refrigerant in it I hear the pressure relief have you ever come across this thanks.
yea I have come across this could be because the coil is micro channel or long line sets